M-mode and two dimensional echocardiography are useful in the evaluation of left ventrical function. However, these techniques do not give information on blood flow parameters as indices of overall left ventricular function. Pulse-Doppler echocardiography, an easily performed non-invasive technique can be used to measure the velocity flow profiles in the heart and great vessels. The objective of this research is to develop and extend the usefulness of pulse-Doppler techniques in the study of left ventricular function. The specific aims are: 1) Further validation and quantification of pulse-echo Doppler techniques. 2) Development of additional technological improvements so as to extend the usefulness of the technique. 3) The study of pulse-Doppler echocardiography in patients in health and disease. This research will attempt to define systolic and diastolic left ventricular performance parameters. Such research should allow a greater understanding of the effects of disease on left ventricular function and develop as a clinical tool this technique for the evaluation of left ventricular function in patients with heart disease.